Hot air furnace circulating means



Sept. l0, 1940. J. H. Russi-:LL 2,214,479

HOT AIR FURNACE CIRCULATING MEANS Filed Deo. 29, 1959 2 Sheets-Sheet 2 Patented Sept. 10, 1940 UNTD STATES PATENT OFFICE 2 Claimse This invention relates to hot air heating means employing the customary hot air furnace in conjunction with a hot air distribution and circulating system. An important advantage of the f invention is that there is no tendency for the hot air within the furnace itself to back up or impede the flow of cold air in the cold air duct leading to the furnace. the invention is that the circulating system is so arranged that at vno time does the flow of hot air have to cross or conflict with the flow of cold air. in the space being heated.

A still further important advantage of the invention is that the cold `air ducts lreturning from mi each of the rooms being heated are brought together to discharge into a common header having a discharge opening into the furnace air heating chamber of such area that regardless of whether or not one or more rooms of the house 20. being heated are closed off, therev will still be .a cold air flow into the furnace through this header discharge opening of sufficient volume to maintain the required circulation of air through the other parts of the house, all Without any stagnation or interference with the discharge and return air iiows from and to the furnace.

These :and other objects and advantages of the invention will become apparent to those versed in the art in the following description of one particular form of the invention as shown more or less diagrammatically in the accompanying drawings, in which Fig. 1 is a side elevation of a furnace system embodying the invention;

Fig. 2, a top plan View;

Fig. 3, a top plan view of the cold air return header;

Fig. 4, a view in side elevation; and

Fig. 5, a view in outer end elevation.

Like characters of reference indicate like parts throughout the various views in the drawings.

Referring to the drawings, the furnace I0 may be of any desired construction, the details of which do not enter into the invention. However,

the furnace l0 will be of that type wherein air is heated to cause a circulation thereof by permitting the warm air to discharge from the upper part of the furnace to be replaced by cold air flowing into the furnace jacket at a lower elevation. In the present illustration of the invention, the furnace is shown as having three warm air discharge pipes Il, I2 and I3, one for each of the three rooms to be heated. These pipes II, I2 and I3 discharge into outlet registers I4, I5 and I6, respectively. The location of A further feature of these registers may be either in theside. walls of the rooms or in the floors thereof, the registers being indicated in the drawings as being in the floor in each case. Some :advantages may be had in placing the registers up on the side walls 5 of the rooms but generally there is insufficient room in the walls within which to place the proper size pipes, or conduits to carry the volurne of air required and hence a compromise is effected by placing the discharge registers on the floors.

Contrary to the practice heretofore had, a cold air return register is placed in each of the rooms having a Warm air register. In the present example, as illustrated by the drawings, cold air registers Il, IS and I9 are indicated, .one in each of the three rooms and are shown as being placed o-n the floor. Conduits 2U, 2l and 22 lead respectively from each of these registers Ii, I8.

and I9 back to the furnace to connect individu- 2.0..-

ally with the header 23 which in, turn connects by a single common connection with the lower part of the furnace to discharge into the air chamber therewithin. As indicated in the drawings, the header 23 is connected to the furnace 2.,.5.

I0 near its base.

The header 23 is herein shown as having a fiat outer end to which connecting nipples 24, 25 and 2B are secured about openings through that end and over which nipples the respective cold 30 air pipes 20, 2l and 22 are tted. The header is then tapered from the outer end back to a furnace connecting thimble 21. This thimble 21 has an internal diameter sufficiently large to take care of the inflow of air coming through the 35 pipes connected to the header without any appreciable. frictional resistance to that flow. As indicated by the drawings, Figs. 3-5, the outer end of the header is rectangular in shape and is tapered principally by the sides back to the thim- 40 ble 2'I.

Assuming that the furnace Ill is in operation and that the warm air registers I4, I5 and I6 are open, in the respective rooms A, B and C, the air discharging from those registers will tend to 45 flow upwardly and finally across toward and to the cold air registers Il, I8 and I9, through which the cooler air drops through the individual pipes 29, 2I and 22 leading therefrom to complete the circulation back to the furnace I0. Where in- 50 stallation makes it possible, the cold air registers I1, I8 and I9 should be placed in parts of the individual rooms farthest removed from the warm air registers I4, I5 and I6. Now should the register I4, for example, be closed and the 55 door to room A be also closed, circulation as between the registers M and l1 will be stopped. However, this stoppage of circulation does not in any way affect the circulation of air between the registers l5 and I8 in the room B and between the registers I8 and I9 in the room C. Since in this case all of the warm air from the furnace l!! then discharges through the two registers l5 and I6, the circulation will be adequately taken care of by the two return pipes. 2l and 2i! without in any way impeding that circulation as would otherwise be the case when the customary single cold air register is employed in one part of the house in one room which may be the one that is closed ofi".

In other words, regardless of whether or not any one or two of the rooms of the three may not be receiving' warm air by reason of their registers being closed, the remaining room or rooms will be adequately heated since the full circulation of air is maintained.

It is further to be noted that by reason of the fact that all of the cold air pipes 20, 2l and 22 being comparatively small in diameter in reference to the heretofore commonly employed single cold air duct, and further, all discharging into the common header 23, the back flow of cold air through any one or two of these pipes will tend to set up an injector action into the furnace tending to draw air through the other pipe so that there is the further guarantee of circulation of air in that roem from which this one other pipe leads even though it be on the Windward side of the house and, of course, with the withdrawal of air from that room, the Warmy air will tend to now in to replace it and thus maintain the circulation.

It is to be noted that should any hot air register in any room be closed, the cold air register still remains open in that room and the cold air may ow from that room to the furnace to insure a maintenance of the proper air supply and thereby extend the life of the furnace by preventing overheating.

While the invention has been shown and described Vin the one particular form, it is obvious that structural changes may be employed without departing from the spirit of the invention and, therefore, it is not desired that the invention be limited thereto beyond the requirements as may be imposed by the following claims.

The invention claimed is:

l. In a hot air heating system for heating a plurality of rooms, a furnace, a hot air inlet register in each room, a cold air outlet register in each room, an individual hoi-l air pipe from the furnace to each hot air register, a cold air pipe from each cold air register to the furnace, a cold air boot having a single wall through which all of said cold air pipes discharge in parallel arrangement, and a thimble interconnecting the boot with the lower end of the furnace, said boot being reduced in cross-sectional area from said wall to said thimble, whereby said boot and thimble form in eiect with said furnace a Venturi tube cold air intake to have the minimum diameter of the tube at the furnace connecting end, so that the cold air returning from the rooms reaches its maximum Velocity at its entrance into said furnace.

2. In a hot air heating system for heating a plurality of rooms, a furnace, a hot air inlet register in each room, a cold air outlet register in each room, an individual hot air pipe from the furnace to each het air register, a cold air pipe from each cold air register to the furnace, a cold air boot having a single wall through which all of said cold air pipes discharge in parallel arrangement, and a thimble interconnecting the boot with the lower end of the furnace, said boot being reduced in cross-sectional area from said wall to( said thimble, whereby said boot and thimble form in effect with said furnace a Venturi tube cold air intake to have the minimum diameter of the tube at the furnace connecting end, so that the cold air returning from the rooms reaches its maximum velocity at its entrance into said furnace, said wall being the outer end wall opposite said thimble to have the line of discharge from said cold air pipes directed toward said thimble, and side walls of the boot sloping inwardly from said rst wall to said thimble.

JAMES HEARN RUSSELL. 

